Amazon.com Brita's Ultra water system not only improves the flavor of tap water for drinking and cooking, it also purifies it. Brita packages two replacement water filters together to ensure that your water filter continues to function properly and that great-tasting water keeps flowing. Contaminants such as asbestos, cryptosporidium, and giardia are removed--as long as the filter is changed regularly. These filters fit readily on the Brita Ultra Faucet Filter, which is sold separately. --Lynne Sampson Product Description Brita On Tap Faucet Water Filter System Filters cut the odor and impurities found in some tap waters to deliver great-tasting water. These filters are BPA-free and are designed to last for up to four months or 100 gallons. The handy filter indicator lets you know that the filter is working and reminds you when a filter needs replacement. One filter can replace up to 750 standard 16.9 oz plastic water bottles, reducing waste and cost. Reduce 99% lead, chlorine (taste and odor) and asbestos contaminants* and get great-tasting drinking water every time you turn on the faucet. Brita On Tap Faucet Water Filter Systems fit standard faucets only. These units do not fit pull-out or spray style faucets. Get great taste, less waste and more savings from Brita. From the Manufacturer Get great-tasting cleaner water instantly with the Brita On Tap faucet filter (fits system model FF-100). The filter has been tested and certified in Model FF-100 by NSF International, the nation's leading testing authority for water filtration products, for ANSI/NSF Standard No. 53. The filter helps reduce the presence of lead, asbestos, Alchlor, 2,4-D, Lindane, Styrene, Benzene, Simazine, Ethylbenzene, Cysts (Cryptosporidium and Giardia), Turbidity, Atrazine, Chlordane, Methoxychlor, Toxaphene, Endrin, Toluene, o-Dichlorobenzene, Carbofuran, Heptachlor epoxide, Trichloroethylene, Chlorobenzene, carbon tetrachloride and Tetrachloroethylne. Filter lasts for 100-Gallons (378 liters) or as long as 4 months, whichever comes first. Filter life may vary depending on local water conditions.